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Visualization Gallery¶
This notebook shows common visualization issues encountered in xarray.
[1]:
import cartopy.crs as ccrs
import matplotlib.pyplot as plt
import xarray as xr
%matplotlib inline
Load example dataset:
[2]:
ds = xr.tutorial.load_dataset("air_temperature")
---------------------------------------------------------------------------
gaierror Traceback (most recent call last)
File /usr/lib/python3/dist-packages/urllib3/connection.py:198, in HTTPConnection._new_conn(self)
197 try:
--> 198 sock = connection.create_connection(
199 (self._dns_host, self.port),
200 self.timeout,
201 source_address=self.source_address,
202 socket_options=self.socket_options,
203 )
204 except socket.gaierror as e:
File /usr/lib/python3/dist-packages/urllib3/util/connection.py:60, in create_connection(address, timeout, source_address, socket_options)
58 raise LocationParseError(f"'{host}', label empty or too long") from None
---> 60 for res in socket.getaddrinfo(host, port, family, socket.SOCK_STREAM):
61 af, socktype, proto, canonname, sa = res
File /usr/lib/python3.13/socket.py:977, in getaddrinfo(host, port, family, type, proto, flags)
976 addrlist = []
--> 977 for res in _socket.getaddrinfo(host, port, family, type, proto, flags):
978 af, socktype, proto, canonname, sa = res
gaierror: [Errno -3] Temporary failure in name resolution
The above exception was the direct cause of the following exception:
NameResolutionError Traceback (most recent call last)
File /usr/lib/python3/dist-packages/urllib3/connectionpool.py:787, in HTTPConnectionPool.urlopen(self, method, url, body, headers, retries, redirect, assert_same_host, timeout, pool_timeout, release_conn, chunked, body_pos, preload_content, decode_content, **response_kw)
786 # Make the request on the HTTPConnection object
--> 787 response = self._make_request(
788 conn,
789 method,
790 url,
791 timeout=timeout_obj,
792 body=body,
793 headers=headers,
794 chunked=chunked,
795 retries=retries,
796 response_conn=response_conn,
797 preload_content=preload_content,
798 decode_content=decode_content,
799 **response_kw,
800 )
802 # Everything went great!
File /usr/lib/python3/dist-packages/urllib3/connectionpool.py:488, in HTTPConnectionPool._make_request(self, conn, method, url, body, headers, retries, timeout, chunked, response_conn, preload_content, decode_content, enforce_content_length)
487 new_e = _wrap_proxy_error(new_e, conn.proxy.scheme)
--> 488 raise new_e
490 # conn.request() calls http.client.*.request, not the method in
491 # urllib3.request. It also calls makefile (recv) on the socket.
File /usr/lib/python3/dist-packages/urllib3/connectionpool.py:464, in HTTPConnectionPool._make_request(self, conn, method, url, body, headers, retries, timeout, chunked, response_conn, preload_content, decode_content, enforce_content_length)
463 try:
--> 464 self._validate_conn(conn)
465 except (SocketTimeout, BaseSSLError) as e:
File /usr/lib/python3/dist-packages/urllib3/connectionpool.py:1093, in HTTPSConnectionPool._validate_conn(self, conn)
1092 if conn.is_closed:
-> 1093 conn.connect()
1095 # TODO revise this, see https://github.com/urllib3/urllib3/issues/2791
File /usr/lib/python3/dist-packages/urllib3/connection.py:704, in HTTPSConnection.connect(self)
703 sock: socket.socket | ssl.SSLSocket
--> 704 self.sock = sock = self._new_conn()
705 server_hostname: str = self.host
File /usr/lib/python3/dist-packages/urllib3/connection.py:205, in HTTPConnection._new_conn(self)
204 except socket.gaierror as e:
--> 205 raise NameResolutionError(self.host, self, e) from e
206 except SocketTimeout as e:
NameResolutionError: <urllib3.connection.HTTPSConnection object at 0x7fbc18bb0ad0>: Failed to resolve 'github.com' ([Errno -3] Temporary failure in name resolution)
The above exception was the direct cause of the following exception:
MaxRetryError Traceback (most recent call last)
File /usr/lib/python3/dist-packages/requests/adapters.py:667, in HTTPAdapter.send(self, request, stream, timeout, verify, cert, proxies)
666 try:
--> 667 resp = conn.urlopen(
668 method=request.method,
669 url=url,
670 body=request.body,
671 headers=request.headers,
672 redirect=False,
673 assert_same_host=False,
674 preload_content=False,
675 decode_content=False,
676 retries=self.max_retries,
677 timeout=timeout,
678 chunked=chunked,
679 )
681 except (ProtocolError, OSError) as err:
File /usr/lib/python3/dist-packages/urllib3/connectionpool.py:841, in HTTPConnectionPool.urlopen(self, method, url, body, headers, retries, redirect, assert_same_host, timeout, pool_timeout, release_conn, chunked, body_pos, preload_content, decode_content, **response_kw)
839 new_e = ProtocolError("Connection aborted.", new_e)
--> 841 retries = retries.increment(
842 method, url, error=new_e, _pool=self, _stacktrace=sys.exc_info()[2]
843 )
844 retries.sleep()
File /usr/lib/python3/dist-packages/urllib3/util/retry.py:519, in Retry.increment(self, method, url, response, error, _pool, _stacktrace)
518 reason = error or ResponseError(cause)
--> 519 raise MaxRetryError(_pool, url, reason) from reason # type: ignore[arg-type]
521 log.debug("Incremented Retry for (url='%s'): %r", url, new_retry)
MaxRetryError: HTTPSConnectionPool(host='github.com', port=443): Max retries exceeded with url: /pydata/xarray-data/raw/master/air_temperature.nc (Caused by NameResolutionError("<urllib3.connection.HTTPSConnection object at 0x7fbc18bb0ad0>: Failed to resolve 'github.com' ([Errno -3] Temporary failure in name resolution)"))
During handling of the above exception, another exception occurred:
ConnectionError Traceback (most recent call last)
Cell In[2], line 1
----> 1 ds = xr.tutorial.load_dataset("air_temperature")
File /usr/lib/python3/dist-packages/xarray/tutorial.py:215, in load_dataset(*args, **kwargs)
178 def load_dataset(*args, **kwargs) -> Dataset:
179 """
180 Open, load into memory, and close a dataset from the online repository
181 (requires internet).
(...)
213 load_dataset
214 """
--> 215 with open_dataset(*args, **kwargs) as ds:
216 return ds.load()
File /usr/lib/python3/dist-packages/xarray/tutorial.py:167, in open_dataset(name, cache, cache_dir, engine, **kws)
164 downloader = pooch.HTTPDownloader(headers=headers)
166 # retrieve the file
--> 167 filepath = pooch.retrieve(
168 url=url, known_hash=None, path=cache_dir, downloader=downloader
169 )
170 ds = _open_dataset(filepath, engine=engine, **kws)
171 if not cache:
File /usr/lib/python3/dist-packages/pooch/core.py:239, in retrieve(url, known_hash, fname, path, processor, downloader, progressbar)
236 if downloader is None:
237 downloader = choose_downloader(url, progressbar=progressbar)
--> 239 stream_download(url, full_path, known_hash, downloader, pooch=None)
241 if known_hash is None:
242 get_logger().info(
243 "SHA256 hash of downloaded file: %s\n"
244 "Use this value as the 'known_hash' argument of 'pooch.retrieve'"
(...)
247 file_hash(str(full_path)),
248 )
File /usr/lib/python3/dist-packages/pooch/core.py:807, in stream_download(url, fname, known_hash, downloader, pooch, retry_if_failed)
803 try:
804 # Stream the file to a temporary so that we can safely check its
805 # hash before overwriting the original.
806 with temporary_file(path=str(fname.parent)) as tmp:
--> 807 downloader(url, tmp, pooch)
808 hash_matches(tmp, known_hash, strict=True, source=str(fname.name))
809 shutil.move(tmp, str(fname))
File /usr/lib/python3/dist-packages/pooch/downloaders.py:220, in HTTPDownloader.__call__(self, url, output_file, pooch, check_only)
218 # pylint: enable=consider-using-with
219 try:
--> 220 response = requests.get(url, timeout=timeout, **kwargs)
221 response.raise_for_status()
222 content = response.iter_content(chunk_size=self.chunk_size)
File /usr/lib/python3/dist-packages/requests/api.py:73, in get(url, params, **kwargs)
62 def get(url, params=None, **kwargs):
63 r"""Sends a GET request.
64
65 :param url: URL for the new :class:`Request` object.
(...)
70 :rtype: requests.Response
71 """
---> 73 return request("get", url, params=params, **kwargs)
File /usr/lib/python3/dist-packages/requests/api.py:59, in request(method, url, **kwargs)
55 # By using the 'with' statement we are sure the session is closed, thus we
56 # avoid leaving sockets open which can trigger a ResourceWarning in some
57 # cases, and look like a memory leak in others.
58 with sessions.Session() as session:
---> 59 return session.request(method=method, url=url, **kwargs)
File /usr/lib/python3/dist-packages/requests/sessions.py:589, in Session.request(self, method, url, params, data, headers, cookies, files, auth, timeout, allow_redirects, proxies, hooks, stream, verify, cert, json)
584 send_kwargs = {
585 "timeout": timeout,
586 "allow_redirects": allow_redirects,
587 }
588 send_kwargs.update(settings)
--> 589 resp = self.send(prep, **send_kwargs)
591 return resp
File /usr/lib/python3/dist-packages/requests/sessions.py:703, in Session.send(self, request, **kwargs)
700 start = preferred_clock()
702 # Send the request
--> 703 r = adapter.send(request, **kwargs)
705 # Total elapsed time of the request (approximately)
706 elapsed = preferred_clock() - start
File /usr/lib/python3/dist-packages/requests/adapters.py:700, in HTTPAdapter.send(self, request, stream, timeout, verify, cert, proxies)
696 if isinstance(e.reason, _SSLError):
697 # This branch is for urllib3 v1.22 and later.
698 raise SSLError(e, request=request)
--> 700 raise ConnectionError(e, request=request)
702 except ClosedPoolError as e:
703 raise ConnectionError(e, request=request)
ConnectionError: HTTPSConnectionPool(host='github.com', port=443): Max retries exceeded with url: /pydata/xarray-data/raw/master/air_temperature.nc (Caused by NameResolutionError("<urllib3.connection.HTTPSConnection object at 0x7fbc18bb0ad0>: Failed to resolve 'github.com' ([Errno -3] Temporary failure in name resolution)"))
Multiple plots and map projections¶
Control the map projection parameters on multiple axes
This example illustrates how to plot multiple maps and control their extent and aspect ratio.
For more details see this discussion on github.
[3]:
air = ds.air.isel(time=[0, 724]) - 273.15
# This is the map projection we want to plot *onto*
map_proj = ccrs.LambertConformal(central_longitude=-95, central_latitude=45)
p = air.plot(
transform=ccrs.PlateCarree(), # the data's projection
col="time",
col_wrap=1, # multiplot settings
aspect=ds.dims["lon"] / ds.dims["lat"], # for a sensible figsize
subplot_kws={"projection": map_proj},
) # the plot's projection
# We have to set the map's options on all axes
for ax in p.axes.flat:
ax.coastlines()
ax.set_extent([-160, -30, 5, 75])
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In[3], line 1
----> 1 air = ds.air.isel(time=[0, 724]) - 273.15
3 # This is the map projection we want to plot *onto*
4 map_proj = ccrs.LambertConformal(central_longitude=-95, central_latitude=45)
NameError: name 'ds' is not defined
Centered colormaps¶
Xarray’s automatic colormaps choice
[4]:
air = ds.air.isel(time=0)
f, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2, 2, figsize=(8, 6))
# The first plot (in kelvins) chooses "viridis" and uses the data's min/max
air.plot(ax=ax1, cbar_kwargs={"label": "K"})
ax1.set_title("Kelvins: default")
ax2.set_xlabel("")
# The second plot (in celsius) now chooses "BuRd" and centers min/max around 0
airc = air - 273.15
airc.plot(ax=ax2, cbar_kwargs={"label": "°C"})
ax2.set_title("Celsius: default")
ax2.set_xlabel("")
ax2.set_ylabel("")
# The center doesn't have to be 0
air.plot(ax=ax3, center=273.15, cbar_kwargs={"label": "K"})
ax3.set_title("Kelvins: center=273.15")
# Or it can be ignored
airc.plot(ax=ax4, center=False, cbar_kwargs={"label": "°C"})
ax4.set_title("Celsius: center=False")
ax4.set_ylabel("")
# Make it nice
plt.tight_layout()
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In[4], line 1
----> 1 air = ds.air.isel(time=0)
3 f, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2, 2, figsize=(8, 6))
5 # The first plot (in kelvins) chooses "viridis" and uses the data's min/max
NameError: name 'ds' is not defined
Control the plot’s colorbar¶
Use cbar_kwargs
keyword to specify the number of ticks. The spacing
kwarg can be used to draw proportional ticks.
[5]:
air2d = ds.air.isel(time=500)
# Prepare the figure
f, (ax1, ax2, ax3) = plt.subplots(1, 3, figsize=(14, 4))
# Irregular levels to illustrate the use of a proportional colorbar
levels = [245, 250, 255, 260, 265, 270, 275, 280, 285, 290, 310, 340]
# Plot data
air2d.plot(ax=ax1, levels=levels)
air2d.plot(ax=ax2, levels=levels, cbar_kwargs={"ticks": levels})
air2d.plot(
ax=ax3, levels=levels, cbar_kwargs={"ticks": levels, "spacing": "proportional"}
)
# Show plots
plt.tight_layout()
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In[5], line 1
----> 1 air2d = ds.air.isel(time=500)
3 # Prepare the figure
4 f, (ax1, ax2, ax3) = plt.subplots(1, 3, figsize=(14, 4))
NameError: name 'ds' is not defined
Multiple lines from a 2d DataArray¶
Use xarray.plot.line
on a 2d DataArray to plot selections as multiple lines.
See plotting.multiplelines
for more details.
[6]:
air = ds.air - 273.15 # to celsius
# Prepare the figure
f, (ax1, ax2) = plt.subplots(1, 2, figsize=(8, 4), sharey=True)
# Selected latitude indices
isel_lats = [10, 15, 20]
# Temperature vs longitude plot - illustrates the "hue" kwarg
air.isel(time=0, lat=isel_lats).plot.line(ax=ax1, hue="lat")
ax1.set_ylabel("°C")
# Temperature vs time plot - illustrates the "x" and "add_legend" kwargs
air.isel(lon=30, lat=isel_lats).plot.line(ax=ax2, x="time", add_legend=False)
ax2.set_ylabel("")
# Show
plt.tight_layout()
---------------------------------------------------------------------------
NameError Traceback (most recent call last)
Cell In[6], line 1
----> 1 air = ds.air - 273.15 # to celsius
3 # Prepare the figure
4 f, (ax1, ax2) = plt.subplots(1, 2, figsize=(8, 4), sharey=True)
NameError: name 'ds' is not defined